Hazumu is born as a boy, who has had a crush on his friend and classmate Yasuna Kamiizumi ever since he first met her. He was not very masculine in either his appearance or his actions, and so as a child he would get teased for being so feminine.
Once in high school, he confesses his love to Yasuna one day, but is rejected. Afterwards, he climbs the nearby Mt. Kashima to clear his feelings. He is fatally injured by an alien spacecraft crash-landing on the mountain. In an attempt to rectify the accident, the alien pilot revives Hazumu but inadvertently changes his physical sex in the process.
After the change and initial shock of those who know Hazumu, it is shown that she has a personality that is very effusive, expressive and quite sensitive which makes her fit well as a Japanese girl. Hazumu ends up becoming more feminine as time goes on, which is shown through her actions, mannerisms and personality. One exception to this, however, is that she never got over referring to herself using the term boku (僕), meaning “I”, which is usually only used by males in Japan.
Hazumu, as an amateur floriculturist, loves plants (more specifically flowers), and is very knowledgeable about them. She is in the Gardening Club, and takes care of a large number of plants around the school campus with the other members though is seen doing most of the work throughout the series.